MY SISTER, MONA, AND I are exactly two years and one week apart. We shared everything - a room with two beds, clothes, toys, birthdays and friends. Though Mona was older, I took on the role of the elder sister. I would help her with homework and explain math problems and books she read. When I was 7, Amma, Mona and I went on a trip to Pakistan. I was the one who gave up my seat, so Mona could be more comfortable. I stumbled down the aisle into the smoking section and found a seat next to a strange man. For the next 13 hours, he chain-smoked cigarettes and drank whiskey. I looked down the aisle and saw Mona stretched out across two seats, comfortably asleep in Amma's lap.

Amma told me that I raised myself. She said that I learned to talk and walk quickly, but Mona struggled at every stage. I climbed trees and rode my bicycle with the neighborhood boys, but Mona stayed at home. She was always crying and throwing tantrums, then getting hit by Amma - sometimes Abba - for her behavior. Mona would throw books at me when she was angry enough. I didn't know it could be any other way.

As a young child, I always searched for stories. I would stuff myself between Amma and Abba in their dimly lit room reciting Urdu letters, while he read medical journals and she watched television. I would rummage around for our past. What did our family do in Pakistan? Farming. How did you and Amma get married? Arranged. Why did you leave England? Didn't like it. These answers reflected off the Journal of General Medicine and Wheel of Fortune were the extent of my history.

By high school, most of the friends Mona and I shared became mine only, and I didn't want to help her with her homework anymore. Amma felt that I had too much freedom and surveilled all my activities. I started skipping school in the afternoons to explore different parts of L.A. - flirting and smoking cigarettes without inhaling. Amma wouldn't let me go anywhere unless I took Mona with me. I started to refer to Mona as "The Warden." I remember yelling at her not to tell Amma what I did and making her cry.

This is when I began to grow apart from my family. Abba and I barely spoke. Bhaijan, who was six years older, seemed so far way from us. By his teenage years, he had become religious, praying mornings and afternoons - just a closed door with a light creeping into the hallway.

Mona and I went to the same school, but I rarely saw her because she remained in remedial classes and I was placed in honors. Mrs. Jackson, my favorite teacher, was one of the few teachers who taught both remedial and honors classes. One day she asked me if Mona was my sister. She said she had tried to talk to my parents about Mona, but they didn't understand. I thought it was a problem with translation - that she wanted to talk to them about Mona's poor grades, her poor study habits.

But I hadn't understood either.

Later that year, we all went to Pakistan. The goal for the trip was well known - to get Mona and Bhaijan married. Within a week, Mona, who was 19, was engaged to our cousin. When she heard the news, Mona squealed loudly and I ran to Abba with inarticulate dread. He silenced me with a congratulatory hug before I could speak.

Later, my brother told me the story. "Don't you know what happened to her?" he suddenly asked me. As if I should have known already.

He told me how in 1971, Amma was pregnant with Mona in England. She was a tiny woman with small hips. The doctor decided that they should try natural birth. In labor - for hours, for days - she pushed. Mona was stuck - unable to come out or go back in. The doctor was unable to pull her out, even though they tried - pulling at her head with clamps. Later, they pushed her back in and cut Amma open.

Bhaijan said, "Mona was born with a bit of brain damage." The room went black and as my head cleared, I found those few words readjusting every memory, every story, every moment I shared with Mona. The image of Mona stuck between Amma's small hips infiltrated my dreaming and waking life. Memories of Mona and I growing up had to be relived with the narrative frame: "a bit of brain damage." Suddenly, I felt deeply guilty for not wanting to take care of her. But then I was angry. Why was I asked to take care of her, grow up next to her, and not be told the truth? Why didn't anyone tell me?

Soon after we arrived back in Los Angeles, I packed my bags to go away to college. I never said a word to anyone about my newfound knowledge until two years later when Mona's marriage was falling apart. I believed that if we talked openly and honestly about her, we could address the real issues in her marriage. But when I finally asked my parents about it, they both responded in denial. "She's just a bit slow," they said. "She's just different." They told me that there was no brain damage. Even Bhaijan told me that he got the story confused.

When Mona remarried, even I joined in saying that "she was a bit slow." I was using their language but felt uncomfortable. I searched for the right words: mental problem, developmentally challenged, learning disability. I wanted a diagnosis. I wanted the answer.

A few years later, I had a candid conversation about Mona with Abba. He said when they first arrived to the US, they thought it was because she couldn't see well and glasses would take care of it. After that, they knew there was still something, but the special schools they looked at housed students with such severe illnesses, that it didn't suit her. He still didn't name what it was she may have.

A few years ago, Abba died and I moved back to live in the same city where Amma, Mona and her family live. I am around them in a way that I hadn't been since I left for college. When I see Mona with her kids - I still struggle with the words to explain who she is.

Bhaijan's son, who is a teenager, came to visit recently, and asked - so matter-of-factly: "Does Mona Phuppo (Auntie) have mental problems?" It was shocking, the ease in which he felt he could address this issue that eluded the rest of us. It wasn't that he was right, exactly, just that he was free enough to say anything at all.

Writer Saba Waheed Illustrator Kyungduk Kim

Saba Waheed is part of the editorial collective of SAMAR Magazine and works as a community researcher by day.